Turtles

I am grateful to the editors of Kachhapa for their invitation to give an outside perspective on the arribadas of olive ridley turtles in India. From a distant viewpoint what I see is waste, waste, and waste.

The first waste is that of adults, often in reproductive condition full of eggs, caught in fisherman's gear, some dead already, others killed to disentangle them from nets, carcasses washed ashore, bloated, rotting. These animals might have contributed to augmenting the next generation of turtles.

The second waste is that of eggs and potential hatchlings on the beaches. The reduction of preferred nesting beaches by erosion, combined with the tendency of the turtles to select such beaches, has led to nesting densities so high that large numbers of eggs are destroyed by turtles nesting subsequently; sometimes as many as 70% of the eggs are destroyed in this way (Mohanty-Hejmadi & Sahoo 1994). Sometimes the production of virtually a whole arribada is lost to high seas. Predators are also numerous, digging up eggs and killing hatchlings. This type of situation is not peculiar to the ridley beaches in Orissa. After arribadas in Costa Rica, sometimes "the stench addled eggs and decomposing hatchlings is overpowering (Hughes & Richard 1974)".

The third waste is that of the opportunity to help impoverished people. The rotting carcasses and rotting eggs might otherwise have provided protein for people in need of better nutrition. Around 35% of the population of India is considered "food-insecure", consuming less than 80% of the recommended minimum energy requirement; Nearly 9 out of 10 pregnant women aged 15 – 49 are malnourished; anaemia results in 1 out of 5 babies dying (World Food Programme 2000).

It is only natural then to wonder whether somehow the situation at the turtle beaches in Orissa could be rearranged in a mutually beneficial way. Sea turtles have a high output of eggs, but poor survival to adulthood. Mortality at the early stages of the life cycle is especially high. The arribadas of ridleys are perhaps the most spectacular manifestation of attrition of eggs and hatchlings. This type of life cycle presents an opportunity for conservation and management: save eggs that would otherwise have been destroyed, allocate some for consumption, and set aside others to augment the output of hatchlings from the beach. This strategy is laid out in general terms in Figure-1.

It is a conservative strategy in that not all the saved eggs are taken for consumption; some go toward increasing recruitment to the wild population. These eggs might have to be incubated elsewhere than the site of arribadas. With attention to such matters as temperature and sex ratio, it should be possible to solve potential problems associated with ex-situ incubation (see also Mrosovsky 1989). Initially, experiments on a modest scale might be advisable. Appropriate administrative arrangements would be as important as the biological aspects.

This general strategy also has the advantage that at least some of the money needed to pursue it would be generated by the operation itself. It is not assumed that no outside funds would be needed; some input might be required especially at the startup phase, but, nevertheless, there is an important closed loop element evident in Figure-1. A project with this structure would generate funds from the sale of saved eggs, some of which could go to government organizations running the project. With funds for conservation being limited, this is important. There should also be a boost to the local economy, and this, plus direct involvement of villagers in conservation and harvesting, would enable the people in closest contact with the animals to benefit from their management.